I am afraid not @alexiom, though this has come up a few times now and I hope we’ll change this soon.
For the time being I shall convert this into a feature request allowing you and other users to vote on having this implemented on the Airtable node.
For a workaround using the HTTP Request node head this way: Airtable multiple select field updated - ERROR: Invalid input for 'XXXXX' [item 0] - #13 by MutedJam